I did a quick search through a few web sources and could only find it identified as a “New Process” 5 speed transmission. Typically found in Chevy Big Bolts, including school buses. I have a 1967 big truck Chevrolet Illustration and Parts book that says it was used in 1956-67 vehicles.
I imagine it has a model number, but my quick search didn’t locate it.
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
NP-540 series, Al top just like 435. Good trans. Some rare ones came w/ OD. Used by Chevy, Ford, Dodge, IHC, forklifts, etc. come with long input shaft for 14” clutch, not very useful for us. Put one in a Early Bronco, Spicer transfer case in another.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
The NP-540 has a shift pattern with Low to the drivers knee and up, reverse to the passengers knee and up, with 2, 3, 4 & 5 in an H pattern between them.
Mike B
Mike Boteler
1956 Chevy 3100 Resto Rod 1952 Willys M38 Army Jeep 1983 Jeep CJ7 Laredo 1984 Jeep CJ7 +++++ Silver Spring, MD
My 1957 GMC 600 wrecker has a NP541OD. And it came from the factory with 232HP. And that was more than the 671 Diesel put out. I had a NP 541 in the 550 GMC I drove 60 years ago. It had the close ratio 4th and 5th. The shift pattern was 4th low axle, 5th low axle, 4th high axle and then 5th high axle. We called that setup a working 5th. And I could run away from just about anyone in those days.
Kenneth: That '57 Olds 370 was only rated at 232 hp?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
I put a 540 in an early Ford Bronco, worked really well, 4th was close to direct, saved having to use low range with a load, 4 top gears used routinely, granny only with a load.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
